1. Field of the Invention
The present invention relates to a thermal transfer image forming apparatus that prints an image by applying heat to a medium using two thermal print heads. More particularly, the present invention relates to a method and device for adjusting the alignment of an image forming apparatus using the distance between two thermal print heads which has been accurately measured using two patterns printed by simultaneously heating a medium using the two thermal print heads.
2. Description of the Related Art
In general, an image forming apparatus converts a document, which a user creates using an application program, or an image, which a user obtains using a digital, camera or the like, into encoded data and outputs the data to media in a visible form.
A thermal transfer image forming apparatus, which is used to obtain a high quality printed image, forms an image by heating an ink ribbon in contact with a medium using a thermal print head and transferring the ink to the medium, or by applying heat to a medium on which an ink layer is formed to reveal a predetermined color in response to heat.
A thermal image forming apparatus may use two or more thermal printer heads to heat a medium and print a color image. If the thermal print heads face each other with the medium between them, such as an upper thermal print head and a lower print head, the print quality is degraded due to thermal interference between the thermal print heads or an increase of temperature in a specific position. Therefore, the thermal print heads are positioned apart from each other.
When the thermal print heads are positioned apart from each other, however, the positions where the thermal print heads apply heat to print a dot of color are not precisely matched. Therefore, accurate color may not be achieved, and the print quality is degraded.
Accordingly, there is a need for an improved method and device for forming an image using two thermal print heads.